The lid is designed for 2 functions, pouring through spout and sucking with PP straw. It can meet your different needs for drinking beverage on different occasions. It’s also easy to get the spout cover open just with one hand, index and middle finger pressing the middle of the lid and thumb unfolding the cover. The leak-proof silicone seal is a security for splash and spill when you put the cup in your tote or car cup holder